1. Field of the Invention
The present invention relates to valve testing apparatus that rotate the valve control to open and close the valve, and more particularly pertains to improvements in valve testing apparatus that facilitate rotation of the valve in a manner that minimizes the potential for damage to the valve during the rotation event, and also facilitates accurate detection and recording of the most pertinent aspects of the rotation event for memorializing the rotation event for maintaining complete records of the maintenance of the valve.
2. Description of the Prior Art
Valves, particularly those used to control the flow of water in municipal distribution systems, spend virtually the entirety of their useful lives in either an open condition or a closed condition, with normally no movement between those conditions, especially if the valve is located underground in a distribution line or on a street hydrant. These long periods of remaining in a single state tends to make it difficult to change the condition of the valve in those few times when change is desired, such as in emergency situations when a leak develops in a pipe connected to the valve. Therefore, it is desirable to periodically “exercise”, or rotate the control stem of the valve between the open and closed conditions not only to avoid freeze up due to long periods of in action, but also to verify that the valve is operational.
A rotation event for a valve being tested typically includes rotating the control stem of the valve from one limit of travel (e.g., the fully open condition) to the other limit of rotation (e.g., the fully closed condition). This cycle may be repeated if desired, but is performed to establish that the valve is still functional.
Further, it has become increasingly desirable to record, both accurately and completely, various aspects of the valve exercising or rotation event. Because the valves to be tested are in typically in widely scattered and sometimes remote locations, the ability to record the pertinent information about the rotation event and bring that information back to a central database containing collected information about the valves is not only highly desirable, but may be critical to keeping valves operational in times of emergency. However, previous valve testing or exercising apparatus have relied heavily upon the operator to locate each of the valves to be tested, and accurately identify each of the particular valves being tested. While data regarding a particular valve rotation event may be recorded in an automated or automatic manner by the valve testing apparatus, the known systems rely entirely on the operator to accurately identify which valve is being tested during each rotation event. If the valve has not been accurately identified by the operator, which is certainly conceivable when the area of a single road intersection may have two, three, four or more different underground valves to be located and tested, the data that is recorded is not associated with the correct valve. Unfortunately, when the valve testing system relies solely upon the operator to identify the valve being tested, it is also conceivable that the same valve could be tested over and over but be “identified” as a number of different valves simply by entering a different valve identification for each “test”, and such abuse may be hard to detect in the limited information recorded during the test.
Thus, there is a need for a valve testing apparatus that is capable of identifying different valves independently of the operator's identification so that mistakes in valve identification do not cause the test data from a rotation event to be associated with the wrong valve.